Mitsubishi Montero (1991+). Manual — part 212

95

C). Disconnect oxygen sensor connector. See Fig. 5. Connect

ohmmeter between heater terminals of oxygen sensor connector as

specified in OXYGEN SENSOR 4-WIRE CONNECTOR TERMINAL IDENTIFICATION

table. This test checks resistance of oxygen sensor heater element.

Fig. 5: O2 Sensor Connector Term. ID

Courtesy of Mitsubishi Motor Sales of America.

2) When oxygen sensor is at 68

F (20

C), resistance should be

approximately 12 ohms (20 ohms on 3.0L models). If resistance is not

within specification, replace oxygen sensor.

CAUTION: DO NOT apply battery voltage to oxygen sensor output

terminals. Damage to oxygen sensor could result.

3) Apply battery voltage to oxygen sensor heater terminals as

specified in OXYGEN SENSOR 4-WIRE CONNECTOR TERMINAL IDENTIFICATION

table. This heats oxygen sensor heater element.

4) Connect digital voltmeter between output terminals

specified in OXYGEN SENSOR 4-WIRE CONNECTOR TERMINAL IDENTIFICATION

table. Repeatedly race engine and observe oxygen sensor output

voltage. If oxygen sensor output voltage is not within 0.6-1.0 volt,

replace oxygen sensor.

OXYGEN SENSOR 4-WIRE CONNECTOR TERMINAL ID TABLE

Heater Output

Circuit Circuit

Application Terminals Terminals

Montero, Pickup 3.0L & Ram-50 3.0L . . 2 & 4 . . . . 1 & 3

POWER STEERING OIL PRESSURE SWITCH

1) Power steering oil pressure switch is mounted on power

steering pump. Disconnect single wire connector at switch. Start

engine.

2) Connect ohmmeter between switch terminal and ground. If

continuity is present with steering wheel in straight-ahead position,

replace switch. If continuity is not present while turning steering

wheel, perform POWER STEERING IDLE-UP SYSTEM TEST. See IDLE-UP SYSTEMS

under IDLE CONTROL SYSTEM.

THROTTLE POSITION SENSOR

1) TPS is mounted to throttle body, at end of throttle shaft.

Disconnect TPS connector. See Fig. 6. Using ohmmeter, measure total

resistance between TPS connector terminals as specified in TPS

CONNECTOR TERMINAL IDENTIFICATION table. If resistance is not 3500-

6500 ohms, replace TPS.

2) Using an analog (needle-type) ohmmeter, measure variable

resistance between TPS connector terminals as specified in TPS

CONNECTOR TERMINAL IDENTIFICATION table.

3) Operate throttle valve from closed to wide open throttle.

If rate of resistance does not change smoothly within 3500-6500 ohms

throughout range of throttle valve movement, replace TPS.

Fig. 6: TPS Sensor Connector Terminal ID

Courtesy of Mitsubishi Motor Sales of America.

TPS CONNECTOR TERMINAL IDENTIFICATION TABLE

Terminal

Application Numbers

Total Resistance . . . . . 1 & 4

Variable Resistance

Montero, Pickup 3.0L,

& Ram-50 3.0L . . . . . 1 & 3

All Others . . . . . . 2 & 4

VEHICLE SPEED SENSOR

1) Vehicle Speed Sensor (VSS) is located in speedometer

assembly. Connect an ohmmeter between sensor terminals on back of

instrument panel. See Fig. 7 or 8.

2) Rotate speedometer cable. For each revolution of

speedometer cable, sensor should make and break continuity 4 times. If

ohmmeter reading does not fluctuate between continuity and no

continuity or if sensor does not make and break continuity 4 times for

each revolution, replace sensor.

Fig. 7: VSS Sensor Connector Term. ID (Montero)

Courtesy of Mitsubishi Motor Sales of America.

Fig. 8: VSS Sensor Connector Term. ID (P/U & Ram 50)

Courtesy of Mitsubishi Motor Sales of America.

MOTORS, RELAYS & SOLENOIDS

MOTORS

ISC Motor

See IDLE CONTROL SYSTEM.

RELAYS

NOTE: For internal wiring diagram of MPI control relay, see

appropriate L - WIRING DIAGRAMS article in the ENGINE

PERFORMANCE Section.

MPI Control Relay (Montero, Pickup 3.0L & Ram-50 3.0L)

1) MPI control relay is located near right kick panel. Check

for battery voltage at terminal No. 10 of relay connector. See Fig. 9.

If battery voltage is present, go to step 3). If battery voltage is

not present, check circuit between relay and battery, including

fusible link No. 1.

Fig. 9: MPI Control Relay Connector Term. ID (10 Pin)

Courtesy of Mitsubishi Motor Sales of America.

2) Apply battery voltage to terminal No. 10. Battery voltage

should not be present at terminals No. 4 and 5. Apply battery voltage

to terminal No. 10, and ground terminal No. 8. Battery voltage should

now be present at terminals No. 4 and 5.

3) Apply battery voltage to terminal No. 3. Battery voltage

should not be present at terminal No. 2. Apply battery voltage to

terminal No. 3, and ground terminal No. 7. Battery voltage should now

be present at terminal No. 2.

4) Apply battery voltage to terminal No. 9. Battery voltage

should not be present at terminal No. 2. Apply battery voltage to

terminal No. 9, and ground terminal No. 6. Battery voltage should now

be present at terminal No. 2. Replace relay if it does not test as

specified.

MPI Control Relay (Pickup 2.4L & Ram-50)

1) MPI control relay is located near right kick panel. Check

for battery voltage at terminal No. 4 of relay connector. See Fig. 10.

If battery voltage is present, go to step 3). If battery voltage is